Dynamo-electric machine and winding therefor



March 26, 1929.-

w. H. POWELL 1,706,818

DYNAMO ELECTRIC MACHINE AND WINDING THEREFOR Filed Feb. 18, 1926 2 Sheets-Sheet 2 Patented Mar. 26, 1929. y

UNITED vsrivrEs' PATENT OFFICE.

MANUFACTURING COMPANY, OF MILWAUKEE, WISCONSIN, A CORPORATION DELAWARE.

DYNAMOrELECTRIC MACHINE AND WINDING THEREFOR.

Application filed February 18, .1926. lSerial No. 89,017.

This Yinvention relates to dynamo-electric machines and windings therefor.

.One of the obJects 1s to provide a Wave type winding in which all of the coils are not Wave wound. `Another object to provide a wind-` ing comprising such la Wave type )vinding in combination with av lap Winding.

p Another Objectis the provision of a winding in which the currents in the Various armature paths Will be equalized Without the use of cross-connectors. Still another object is p the provision of a Winding in which the potential rise from one brush to another measnred frein bar to bar on the commntator Will `form a substantially smooth curve.

Still another object is the vprovision of an arma-ture for machines in Which taps or phase connections are necessary such as in machines ol'l the three-wire type, or rotary converters and inA which no externalr cross-connectors are necessary. t A further object is to provide an armature with combined lap and Wave type indings which may be used for rotary converters or other machines involving taps or phase connections. A stillr further 'object is to provide awinding :for machines oi `the hereinbefore mentioned character in which heating o'if the Winding at the taps or phase connection points is avoided. i

A still further object is to provide windings or' the hereinbefore mentioned character in which the number oit' circuits or paths in one component o'l the` winding is equal tothe numberv in the other component.

Other` objects 'will appear hereinafter as the description of the invention proceeds.

y 'The novel 'features of the invention will appear `trom vthis specification and the drawings accompanying the same and forming a part thereof, and showing one embodiment of the invention, and all these novel features are intended to be pointed eut inthe claims.

In the drawings:- p

Fig. 1 is a diagram of, connections for a rotary converter armature.

Fig. 2 is a plan view of a Winding element which may be used in a machine such as shown in Fig. 1.

3, 3b, 3c and 3d are fragmentary plan views of portions of another form of winding element which may also be utilized in a machine such as shown in Fig. 1. v

- Figs. 4a, 4b, l" and 41d are fragmentary side elevations of Figs. 3a to 3d inclusively, respectively.

In Fig. 1 the invention'has been shown as it may be applied in a rotary converter armature. For the sake of simplicity a comparatively small nnmber o commutator bars'has p been chosen, namely, 4S. For the same reason the number of slots is also shown as 4S. The

machine isshown as provided Wit-h six slip rings A19,50, 51, 52, 53 and 54, the particular machine illustrated being va 6-pl1ase, l--pole machine. i,

The armature is here shown as provided with a combined lap and Wave typew'inding. The lapwinding is indicated by the dotted lines. The Wave type winding has its Wave Wound conductors indicated by the light full lines.` As will appear hereinafter all of the conductors belonging to the Wave type winding do not constitute yWave wound coils. The armature here shown has a total of 192 conductorsthere beingtconductors per slot, as indicated by the circles arranged in radialrows. 96 o1 the conductors are connected to form a lap Winding which in the illustrated exan'iple lis of the simplex vtype inasmuch as if We start tracing the lap Winding from any given commntator bar We Will pass through allof the `96 conductors allotted to the lap winding before We reach the bar at which We started. It Willv be noted, in tracing the lap Winding that We includeinthis Winding the coils 1, 5, 9, 13, 17, 21, 25, 29, 33, 37, 41 and 15 which are here drawn in heavy full lines for the purpose oi distinguishing them from the other conductors. These hereinbefore mentioned coils are common to both the lap winding and the wave type winding, as will it, beginning for example, at connnutator bar 5 appear hereinafter.

T he nature of the wave type winding will be best understood by tracing at least a part ot 1. For this purpose reference may be had to the following table:

Referring to the line in the table marked Bars (lV. T. 7.) this enables tracing of the wave type winding 'fron'rbar to bar beginning at bar 1, the nmnbers indicating the commutator bar numbers. Then we reach bar 22, instead of continuing to trace the winding in a clockwise direction, we pass in a counter clockwise direction through coil 21 to bar 21. From bar 21 we again trace in a clockwise direction through wave wound coils to har 42 and 'from there counter clockwise through coil l1 to bar 41 and from there again clockwise through several. wave-wound coils, as indi-` cated in the table above, to bar 141 from which we pa ss counter clockwise through coil 13 to bar 13 and so on. As was previously stated, the table is not a complete one tor the winding inasmuch as the complete table .is too long and y is not necessary for a complete understanding ot the invention. It will also be noted from the table and 'from an actual tracing of the lap winding that coil21 is symmetrically placed with respect to coil 15 the latter being connected to bars 4175 and 116. Coils 21" and 415 are here shown as provided with phase connections leading tol slip ring 50. It the wave type winding is completely traced it will be iound that the coil 4:5 will be eventually reached and traced through in a manner si1nilar to that already described. in connection with the partial Wining table. leiter-ring again to the table, the connection of the .lap winding from bar to bar is shown at the line marked Bars (lap) lt will be noted that those bars in the lap and wave type windings that have. connected thereto coils to which phase connections maybe applied are otlset so as to make them readily distinguishable. The lap coils are indicated in the `first line of the table marked Coils (lap) by a double infimed number corresponding to. the reference nunicrals in Fig. 1..u The lap coils have been numbered arliitrarily as havin the same .number (but double primed) as one of the eouunutator hars to which theyare Aconnected as for example from bar 1 we pass to lap coil 41S to bar 4S. to coil 17 to bar 4:7, etc. i The coils` of the wave type winding traced through in using the table `for Bars (W. T. 7.) are indicated at the line marked Coils (YV. T.

7.), that is, from bar 1 we pass through Wave wound coil 1.2', from there to bar 2st, 60 from there to wave wound coil 35 and so on. It will be noted that thc wave wound coils have been indicated by primed numerals,

whereas the lap wound coils are double primed` It will now be clear that the lap wound coils indicated by the heavy full lines in Fig. 1 are common to both the lap winding and the wave type winding, and that, in the winding shown, coils 360 electrical degrees apart are connected to the sanie'slip rings.

The wave type winding has been hereinabove arbitrarily traced generally 'in a clock-- wise direction. The winding could oit (nurse have been traced in a couiiter-clockwise di rcction. The direction ot tracing does not, however. change the character ot the winding. The Vwave coilsI in the illustrated. enibodiinent ot the invention have a commutator pitch which is less than the equipotential pitch and the winding is tllcretore termed a retrogi ssive or lett hand winding. lli the cominutaior pitch were greater than the efp'lipotential pitch the wiruling would be called a progressive or right hand winding. The lap coils, in the illustrated embodiment7 having a back pitch greater than the front pitch, are o'l the progressive or right hand type. In general. it the wave winding progresses 'in one direction the lap winding should progress in the opposite direction.

In tracing the wave type winding through completely trom any given bar such as bar 1. it will be Yfound that we pass through 2)(5 conductors, that is. all ot the comluctors belonging` to the wave type winding betere we again reach bar 1. he windingl is theretm'e oi the simplex type but it is doubly reentrant and therefore it has tour circuits which is equal to the number o t circuits in the 1f-pole lap winding. There should be such a prcde- 'tei-mined number ot wave type windings, whether one or more. and the individual rccntrancies oi the wave winding should be such that thc number ot circuits in the wave type winding collectively is equal to the total number ot circuits in the lap wini'ling.

l'n considering the points on the winding where tap or phase connections are made, a

` consideration of one of these places will be sufficient for all. Referring to coil 1, Fig.

y1, it will be noted that the active conductors current through conductors g and 71 these vlatter conductors, as also y and L, being respectivelyl connected to each other. It is clear that, for' example, conductors g and L could be combined into one single copper bar. Itwill be notedthat considering for example, the "front end connections for lthe lap and wave type windings that theyy are arranged in tour concentric layers, the radially outermost and radially innermost layers being occupied by end connectors belonging to the wave type winding whereas the two intermediate layers are occupied by end connectors of lthe lap winding. This is of course true where the end connectors reach the radially extending commutator necksto which they are connected. It is therefore desirable that an end connector Yleading from the combined conductor lrj-t' should Ipass into the layer of end connections presented by the conductor g. f f

It will be notedthat it thearm'ature Winding were ot' the unmodified lorm ot' combined lap rand wave winding such as illustrated 4in applicantscopending application S. N. 713,- 723 tiled July 24,` 1923, (nowePatent No. 1,628,611 issued'May 10, 1927) coil 1, for example, would be made up of two coils one ot which has .its conductor so Wound as to form a V.lap coil and the'other a `wave coil. phase connection were made only tothe lap coil or only to the wave coil either oi" these coils would Vheat almor'mally. Onthe other hand it would notbe possible to make the phase connection to both ot these coils tor the reason that such lap and wave coils have their coil. sides connected to points of opposite poi tent'ial on the eommutator. VIt will beobvious therefore that the winding here disclosed obviates these difficulties while retaining all oit the advantages set forth in ap It' theV per slot, 6 ot which are lap coil sides and (3 of which are normally wave coil sides. It', as shown in Fig. 2, the lap and wave coils have the same pitch, they may be taped up together to form a singletorni-wound element; vThe upper terminals connectible to the comn'iutator necks, of the lap coils here shown, are designated (L, o, c and the lower ones ai, c. In like manner the wave coils are designated el, c, and (Z, e', f. It will be understood that the end connections d, e, f and d', e', f will be in the radially outermost and radially innermost concentric layers respectively, whereas the end'connections a, c and a', b', c will be in the intermediate layers respectively. The coils as shown in Fig. 2 might be termed normal coils whereas the coils provided at the phase connection points are of diierent form. These latter coils are wound as shown in Fig.` 3f to Fig. 3 inclusive. Fig. 3 is a plan view ot that portion of a phase connection coil corresponding to the part ot the normal coil. Fig. 3b, Fig. 3C and Fig. 3 are plan views ol the portions ot a phase connection coil correspending respectively to the portions 56, 57 and 58 of the normal coil. `Considering Fig. Sffirst, there are 3 conductors u, o, w in the radially outermost layer and conductors y, e inthe next to the radially outermost layer. The conductors o, fw are Wound so thattheir end connectors turn, as viewed in Fig. 3b, in a downward direction. The conductor u on the other handis bent radially inward as shown in Fig. 4b and' then passes along with the lap type end connections w, y, z.- Following.thisconductor u, to Fig.V 3u, it there is bent so as to pass out of the layer of lap type end-connections y, e radially out ward (asshownin the side view Fig. 4a) into the radially outermost layer of commutator terminal connections, which `latter corre` spends to the normal position of the terminal connections for the normal vwave Wound coils as represented by Fig. 2. Tracing the conllt) ductor @toward the back endconnection we f tindthat, as in Fig. 3, it extends slightly beyond theV U-bend of the normal coil and in the construction here shown appears in side elevation as shown in Fig. l, theconductor being bent at some desired 'angle to form a terminal connectible to a predetermined slip ring.l Theback end connection of the other side of the coil u begins as a terminal for the same slipvring and lproceeds a'conductor u" toward the commutator and at that portionl oi the coil corresponding to the portion 58 ot the normal coil it is bent radially outwards into the next` radially adjacent layer l occupied bythe lap coil end connections y', e which correspond to the conductors w, In like manner,- the lap coil 'av-ew is formed to provide back end connections con-` nectible to a slip ring as shown in Fig. 4c.

It will therefore be seen that the conductors '1n-zt `which in the normal coil would be 'formed to constitute wave wound coils are, in the special coil, formed to ctmstitute lap wound coils. The coil n, u while it is a part ol the cfmtinrmus ware type winding, as has been hei-eil)beh-)re shown in connection with Fig. l, is' electrically also a part of the lap winding particularly as to current flowing to and from the phase connection. Y This is also truc as to the coil U-ic. Y.ither one o'lE these coils or both ot' them together may therefore be regarded as coils conm-ion fto either the lap or wave 4type winding.

It will he clear that lit is not essential that the wavevand lap wound coils occupy the particular concentric layers as illustrated but that, :tor example, the `lap `wound coils might occupy the radially outermost and innermost layers.

It should be understood vthat it is not desired to limit the vinvention tothe exact details ol construction and operation shown and described, 'for 4obvious modifications will occur to persons skilled in the art.

It is claimed and desired to secure `by Letters Patent:

l. An'aianature provided with a predetermined number of slip rings, a winding 'for said arn'lature, a lpredetermined number oit equalizing connections for said winding including acti-ve winding elements, and a connection -from one ort said rings to a portion of said winding -and to oneA ot' said cqualizing connections. v

2. An armature having its conductors connected. `to form ii-espectively a lap type winding und fa -wa-ve ltype wind-ing connected' in parallel, a predetermined number of said conductors kless than the total number being common to both thelap and Wave type windings, a `given wave type circuit of said armature containing a predetermined number of lap coils alternating with groups of series connected wave coils each oi said groups containing more than one coil.

3. An armature provided with a commutator and a predetermined number of slip rings havin g its conductors connected to 'form respectively a lap type and wave type winding, a predetermined number of said conduetors being common to both the lap and Wave type wimlings and a connection from one ol said ringsto one of said common conductors. i

4. Aicommutator type armature winding havingvits conductors connected to form a wave type winding, a predetermined number oi. said conductors less than the total number liavingtheir terminals connected'to said commutatorto iiornrlap'coils, a given wave type circuit'of said 4armature containing a predetermined number of lap coils alternating with groups of series connected wave coils each of said groups containing more than one coil.

f5. A comunita-tor :type armature having its conductors connected to form a wave type winding, a predetemnined number of said conductors having their terminals connected to said commutator to form lap .coils in series with the waveconneeted conductors, said lap connected and wave `connected conductors having slot pitches and terminals having armature pitches such that the la p connected coils progress in a `direction opposite from that ot' the wave connected coils.

6. A con'nnutator type armature having its conductors connected to form respectively a lap winding and a wave type windingga predetenmined number of the conductors less than 'the total number of said wave type -w-inding having their terminals connected to said commutator to fonm -lap coils, Aa given wave type circuit of said armature containing a predetermined number of la-p `coils alternating with groups ofseries-connected wave coils each of said groups containing vmore than one coil.

7. Aconmiutator type armature having its conductors connected to forni respectively a .lap winding with the conductors having slot pitches and terminal connections to the commutatorsueh :that the winding progresses in a'giaiendirection and a wave type winding with wave connected `conductor terminals having a comniutator ,pitch such vthat the winding 4progresses generally in theiopposite direction, a predetermined number oetl conductors ol said wave type 4winding having their tenminalsiconneeted to said comnmtator to form lap coils progressing -infthezsame directionns said lap Winding.

8. A'cominutator :type armature having its conductors connected vto form respectively a lap winding .and Va predetermined number of Wave "type windings, the number of wave type windings :be-ing such -and individual reentrances such that the `total number of cir cuits in said predetermined number of Asaid wavetype windings equal to the total number of circuits in lthe lap winding, a predetermined number of conductors of said predetermined number of wave type windings having theirlterminals connected to said commutator to form lap coils.

9. A rotary converter type armature having its conductors connected to orm respectively a lap winding and a predetermined number of wave type windings, the number of wave type windings being such and the individual reentrances such that the total number of circuits `in said predetermined number of Wave type windings is equal to the total number of circuits in said lap winding, a predetermined number of conductorsvof said predetermined number of wave type windings having their terminals connected to the 'commutator to form lap coils located at the phase connectionipoints.

lll)

10. n an armaturehaving induced conf ductors, front end connections and commu tator connection terminals disposed in concentric layers, a predetermined number of said induced conductors having their end connections disposed in layers other than those in Which said predetermined number of induced conductors are disposed and having their commutator connections disposed in layers corresponding to those in which said predetermined number of induced conductors are disposed.

11. In an armature including the lap Winding and Wave type Winding having the coils thereof disposed in concentric layers, a predetermined number of coils in said Wave type winding having lap type end connections disposed in the layers in which the end connections of said lap Winding are located.

l2. In an armature including the lap Winding and Wave type Winding having the coils thereof disposed in concentric layers, a predetermined number of coils in said Wave type Winding having lap type end connections disposed in the layers in Which the end connections of said lap Winding are located, and having the commutator terminals of said end connections disposed in the layers in which the end connections of said Wave type Winding are located.

In testimony whereof, the signature of the inventor is affixed hereto.

VILLIAM H. POVELL. 

